Strained gate-all-around semiconductor devices formed on globally or locally isolated substrates

A method of fabricating a semiconductor device, the method comprising:

• forming a three-dimensional semiconductor structure on an epitaxial seed layer disposed above a semiconductor substrate, the epitaxial seed layer comprising a semiconductor material different from the three-dimensional semiconductor structure;
• etching the three-dimensional semiconductor structure to provide a three-dimensional channel region and to expose portions of the epitaxial seed layer on either side of the three-dimensional channel region;
• forming source and drain regions on either side of the three-dimensional channel region and on the epitaxial seed layer;
• insulating the three-dimensional channel region and the source and drain regions from the semiconductor substrate by forming an insulating structure comprising one or more isolation pedestals continuous with the semiconductor substrate;
• and, subsequently,
• removing a portion of the epitaxial seed layer;
• forming a gate electrode stack at least partially surrounding the three-dimensional channel region;
• and
• forming a pair of conducting contacts, one contact at least partially surrounding the source region, and another contact at least partially surrounding the drain region.